Weird 49cc Issues (Motorized Bike)

With bad weather I have some time to dig into some of the older motorized bikes.
What I found was annoying...
We also take the Sothern Custom CC Hybrid for it's first ride.
Sothern Custom CC first inspection video: • Tearing Down The SCcc ...
We upload motorized bike videos every week (sometimes more)!
FAQs:
Oil: 32:1, semi synthetic, random brands.
Gas: 87oct
Spark Plug: NGK B8HS (yd-100), NGK B6HS (pk80)
Parts: I buy mostly from Amazon.
Favorite Motor: Zeda (Firestorm) Triple 40
Favorite Carburetor: NT Speed
Favorite Bike For A Motor: I don't have one yet.
To contact me directly find me on Discord "LA Hover#1036"
For motorized bike help, join the server / discord

[@lengaming1651]

Did you check the lower crank pin bearing for any side to side slack? The pin might not be seated as far as it should, causing each half of the crank to be spaced a litte too far apart. Dealing with that is not an easy job though...

[@LAHover]

Good call, that looks like the issue :) just got to find a press...

[@lengaming1651]

@@LAHover Oh, lucky guess! Glad to help

[@evenbuzzard4642]

Is the big clutch gear supposed to be slightly loose?

[@joneserupinsmoke9161]

@@evenbuzzard4642 not to sure but I would think the pads should not be rubbing on the back untill pressure force

[@johndoelman266]

25:33

[@kjsmolik]

That Smolik Perfoemance head is a piece of art

[@LAHover]

Indeed :) looking forward to running it!

[@Rudy97]

Forstner bit, drill press and a good vice is all you need to get the bearing to go deeper. The case is soft enough to drill it down a hair.

[@JMB676]

Well take what I say with a grain of salt as I'm not there touching the motor n components. However I personally have gone to great legnth (making super thin spacers) to not run two gaskets or even better no gaskets where ever and whenever possible so I definitely vote for not using multiple gaskets I believe the only opythen is material removal which is very hard to be precise but if you did remove a hair to much you can alwatput in a shim to take up that space. I actually had to make one for my 50cc I'm working on right now for total opposite reason. Mine had to much play. Maybe to fix both our problems I just mail u the left side of the motor n u mail me your left side then boom we both have proper tolerances lol 😂.

[@clownfishing1980]

I would like to see you fix the 49cc motor l believe it would help people because if they have the same problem Great work

[@HanzelFonferek]

There's always something to keep ya on your feet with a Motorized Bike, well not necessarily since you ride the bike! Lol! You get the point 👍

[@smh3132010]

Same bike I have with a 80cc motor. Been running good for 5 years so far.

[@LAHover]

Nice work keeping it running for so long :)

[@smh3132010]

Thanks man :) Hopefully it lasts a bit longer. I'll probably try and rebuild it once it breaks. With help from your videos I'm sure.

[@sundial6919]

The 49s need love too . Missed seeing the shows directer , Henry though

[@413MassDigger]

awesome vid bud, Beginning was hilarious lol!! Id like to see the 49cc running again

[@radiowavz]

Look at getting a ultrasonic jewelry cleaner. Perfect for small parts and bearings using the mineral spirits. Also simple green as a degreaser in the cleaner.

[@sundial6919]

The simple green is great degreaser my fav but can discolor aluminum and ruins finish on polished aluminum

[@HanzelFonferek]

Great video as always bro!

[@yzstormer]

Well, hopefully you can get that 49cc running! Great work as always.

[@keithfreeman5204]

Had a problem with a 80. Crankshaft bearings. Remove one of them and took it to NAPA, found a German bearing that felt very smooth. Got two bearings , installed them, reassembled the engine. Much higher top end, mid range pull is great. Beginning of my 5th Summer of working/building these small 2 stroke engines. Probable the most important thing I learned, no matter the engine, is, WARM these engines up 100%, heat saturation is really important before asking them to do anything. Doing this will help your engines to last much longer.

[@matouslitera8073]

Great first ride impression hover. I could hear the vibration in the motor. My AF80 bottom end has stripped a bolt. I hate dealing with this. I could probably helicoil it? It's the long top case bolt on the front (exhaust side) of that case. The threads were cut before painting and not retapped afterwards, hope to fix it.

[@sanbyakuman]

Great instructional video. Now I know what to look for if my engine makes a humming noise.

[@keeganhache6667]

Lol in Canada we get like 20cm of snow on a normal day

[@keeganhache6667]

@itscorcor umm research what do you mean. I make my bikes go fast just in the summer

[@randomprecisionmotors3130]

That's ok, we had a bridge wash out back North in a Flood in 2010, and because it was going over a border between Ct. and R.I., they fought back and forth for literally a Decade before the bridge FINALLY reopened last year in January! And wouldn't you know it, me and my first build were the FIRST motorized vehicle to go over the new span, and it wasn't officially opened for another 3 months after that!

[@KenC56mm]

Your minarelli build sounds So much better with the Mz! So much better. Love that sound! I'll stop complaining about the sounds of your builds now 😁

[@kenjuicekrajewski9577]

Sounds real strong for a 49cc great videos as always

[@tinypurplefishesrunlaughin8052]

Yep after 3 years of heavy use I started a full blown modification, started with moderate porting of intake exhaust including transfer ports, added an expansion chamber and learned how to properly jet the HP carb to get a nice semi lean burn, this really optimized the powerband and it continues to pull hard from 3500 to 8500 then suddenly drops off. I believe slightly increasing chamber size will cure that but if not no big deal as I’m moving towards 50 mph with the stock 39 tooth so I can always decrease teeth gaining speed lowering RPMs until the dead spot never is realized. Always using premium two stroke oil ( Bel-Ray

[@KenC56mm]

Ive had to do this on almost all my builds to free up the crank: Lighly tap on the side of the crankshaft with a hammer straight-on meaning towards the other side of the engine. Seriously. That will take any tension that might be in-between the bearing, crankshaft, and case. Then tap the other side in the same way, towards the otherside of the motor, Keep doing it over and over until the crank spins freely. There's been times that I've actually had to hit one pretty hard to free it up. You'll end up discovering that you didn't need an extra case gasket after all.

[@KenC56mm]

Warning! I forgot to mention to make Sure that you place a wedge in between the crank webs or it could knock the crank out of true by tapping too hard on either side of it.

[@RedpaceIII]

I'd be super excited to see if you solve the 49cc riddle. Great video.

[@LAHover]

some viewers pointed out the the crank might not be pushed together enough, and that looks like the issue.

[@RedpaceIII]

@@LAHover thanks. I've gotta tear down a 49cc that has never seemed to have as much power as it should and was glad to get to watch a video about it. You da man

[@drpc97]

Just got mine running today. after 1 1/2 years of sitting in hot summer and N.E. Ohio snow. It turned over on second try! no pedal bike chain on it either. i was amazed of it.its been running since 2018 as a daily driver around a small town.

[@rockyrococo2584]

One of my first motors was a mid 2000's ebay 49cc someone gave me used. It ran for about a year and I had the same exact failure and ran into the same tight crank issues. Along with bigger crank bearings and an odd hard as hell to find sized crank seals. I found one distributor in Australia that was like $60 to ship to use. It tool me forever trying McMaster and other suppliers to find anything but eventually found two close enough widths to work. The magneto was a specific Stihl crank seal but I forgot what I found for the drive gear seal seal. They're pretty obsolete at the price difference and never go back but they are fun if you got one and work the kinks out.

[@madeljacky]

This is simple to fix, press your two flywheels together a hair more on the big end pin, then you shim if necessary the crank end float with shims behind the 6202 crank bearings.

[@gotnitro4329]

Always save old bearing to help you seat clutch bearing back into the case if you don’t have a big enough socket to seat them

[@air-driveaquaponics204]

I have a 49cc as well. Same issue. I actually ground the bearings to 10mm wide. (I don't recommend this) The only other option on an engine with this condition is that the crank may not have been pressed together correctly or the lower con rod pin was too long to begin with. This will cause bearing interference inside the crankcase. Additional gaskets are never the answer. Hope this helps.

[@gasnxt6805]

I would take to the crank case. I would try using a router. Such low cost engines like these allow us to do things we normally would not even think of doing. Even some stopper on your dermal .

[@Tinkerman.45.]

I enjoy your video's so much I went bought a Cranbrook from Walmart a Seeutek motor kit.Have not rode it yet just hate to mess it up.I love 2 strokes reminds me of a 50 cc Harley Davidson motorcycle had one time.I built a lot of bikes with 250@ 350 watt chain drive motors they lot fun.Maby you should try one sometime I made front and rear wheel drive with these motors.keep up the videos I enjoy them.

[@bryduhbikeguy]

That's a heck of a problem with the bearings and case.Without multiple measurements to compare the cases,and crank sizes,there's no real telling if it's just bored improperly,or if the crank's too wide by a couple thousandths.Damned in all directions.Good luck.

[@johnhudson6920]

I'm still riding brother! Cortland NY. 6in of snow, or 96 and sun, it's still gotta go.....soooo much fun on my 21in all steel rigid framed gt outpost, Zeda triple 40, 24mm pwk, boost port, shark head, imitation xpansion chamber, if it don't go straight, lil sideways works too, wooooh

[@kjsmolik]

I use the stage 3 clutch from RDM with 5 of his hard pads. I dont have any issues idling. .it will idle as long as I let it . Upgrade the clutch plate and pads. Youll be good .

[@jmw3253]

How do you mount your 360 cam at the rear. You once said that there wasn’t a good 360 stabilization cam to mount to handle bars. I can confirm that the GoPro Max does very well with stabilizing the video from the handlebars and vibration. Thank you for your videos. They’ve been very inspiring and great to watch.

[@mbnr26]

there's a few people who have made a cheap super clutch. would like to see if your able to do it

[@k.c.7394]

is it the paint on the inside of the case, or insufficient clearance around the crank and housing during rotation, looked like at 12:03 you could see where it was rubbing

[@stephenjohnson6967]

I'm really enjoying your videos. I just found your channel about a month ago and have already watched many of them. You haven't steared me wrong yet. I watched your videos about clutch problems I thought they were very thorough however, my issue wasn't covered. My clutch bevel gear teeth grinded off to the point that they won't engage the other gear. Do you know why this may have happened? I know they require grease but not sure which grease to use. I tried Red n Tacky #2 it didn't seem to hold up well so I cleaned it up and tried white lithium and that was worse. Any advice would be greatly appreciated.

[@caduceus33]

You can use four gaskets and spray each one with copper gasket sealer.

[@KevinTodd]

press your crank together a tad bit

[@LAHover]

Good call, might do the trick :)

[@Centar1964]

How much space between the counter weights on the crankshaft? If there is enough wack/hammer/press the two a bit more together...

[@riverseden5051]

Did you measure the width of your crank from the outside left bearing to outside right bearing and compare it to the inside case dimension? I bought a 50cc engine kit and noticed the exact same issue. Bearings wider than the case. Low end con rod has a bit too much play. Could possibly be resolved with either narrower bearings or a shorter con rod pin

[@christiansanchez1486]

The Phantom 85s are back in stock if anyone is curious

[@joshuayaddowmotorizedbicyc7708]

yeah its been below zero temperatures for the past 2 months i need to move to southern or western states

[@mbnr26]

id really like to see you try build an electric hub motor bike with a cheap kit. 1000w 48v and then add a gas motor to it to make it a tribrid lol

[@novavroomvroom6809]

Screwing something up in a good way can become a great thing...!!!!!

[@LAHover]

lol :D

[@clutch6654]

Make a Metal Gasket and two paper ones...

[@theodoredionne9537]

ID like to see what happens with this motor, im having the same issue on my 66cc, went from an AF-80 crank to a FM-80 crank, turns out its 5mm wider overall. I'm currently waiting on 1-2 case gaskets to fill the missing 1mm of space i need, otherwise its too tight & hard to turn. ill most likely post an update on this comment thread, Might seal the multiple gaskets to eachother to cut down on failure points & add thickmess, Theyre cheap so why not

[@motorizedbikeenthusiast6880]

I have painted 50 cc motor its quite similar to this do i need to watch for this?

[@cedarvalleyrail8419]

A little while back I bought the black motor, expecting to have to do a complete teardown, but I guess you just got a bad apple because it's been running flawlessly ever since it got broken in, I bet they corrected the error later in production

[@LAHover]

Looks like the cranks were not pressed together enough.

[@Zane.Wellnitz]

Sand a little off of the bearings using a sharpening stone.

[@cannonandre9513]

dude whos watching fit mc in the background? nice video

[@LAHover]

You got some good ears :) ... Some times the Minecraft bug bites and I play, or watch other people play :P

[@cannonandre9513]

@@LAHover Nice I like fit mc's videos

[@maxhearld1035]

I am actually really interested in just how much power you can squeeze outta that 49cc I'll bet it's more than you would expect

[@tinypurplefishesrunlaughin8052]

I saw a vid about 20 hp ! Crazy

[@user99524]

@@tinypurplefishesrunlaughin8052 can u send a link i wanna upgrade my 49cc 4 stroke

[@user99524]

@Lane AWD ye u can also put heavier valve springs in

[@michelevitarelli]

How are you filming yourself? Where is the camera?

[@diydad5067]

Regarding 49cc bearing issue, I would start with less invasive procedure first and use 3-4 high quality gaskets or custom made thicker material gasket. If the gasket fails however, then you can go ahead with a hole saw with corresponding size of the bearings then smooth it out with a dremmel tool. I’m curious about longevity of the gasket trick; it will be a good case study. My guess is that the gaskets would survive since the pressure is less compared to head gasket.

[@LAHover]

Crank weights were not pressed together enough. But thanks for the feedback!

[@diydad5067]

@@LAHover Glad you sorted it out without compromises.

[@grifonks]

Double check your bearing thicknesses. It makes no sense that the first crappy set fit and the second set doesn't. Unless the crank lobes moved out under the tapping. I have seen Stihl chainsaw crankshaft clutch hub bearing seats deform from over tightening under the clutch and the steel in Stihl, lol, has to be better. BTW any plans for using a knockoff Stihl MS660 jug on a hybrid?

[@sundial6919]

Any idea where a holzfforma g372xp could be leaking air , new outta the box ? Ive seen others complaining about air leak on g372xp too ?

[@tylergriffin8299]

I wouldn’t sand my crank you want that press fit next time I would put my crank in the freezer set the bearing out in the sun . Where it just gets warm anyways leave the crank in the freezer for atleast 6 hours it will go together easy

[@novavroomvroom6809]

Use it as a parts motor and or a door stopper...!!!!

[@KenC56mm]

That lip is wear from the seal I believe.

[@paradiseviews1533]

Hey my motor is leaking dirty oil out of the exhaust manifold area, would that say I'm running to rich on oil? Or to rich on both fuel and oil? Should.i run with low oil for a couple tanks?

[@LAHover]

Tells me the exhaust gasket is leaking if it's right at the manifold. Most of us run these to rich, but it's safer than to lean... I run 32:1 mix with about a 68 main jet on the NT carb. This motor may have a smaller 62-65 jet I'm not sure.

[@oldstyleanalog6459]

Dude heat the cases and freeze the bearings for 24 hrs.and heat the bearings with a small can toorch.and ur bearings will.go fine

[@michaelnixon3364]

I accidentally bought a bp6hs instead of a b6hs do you think its still be fine to use in place of the zeda 80s stock spark plug are atleast as a potential replacement in the future

[@LAHover]

I don't know much about the different plugs, but the heat ratting should be the same. So as long as the plug does not contact the piston it will probably run just fine.

[@jamesgnarkill3112]

Yup no riding here today....I just got the mz65 for my minarelli. Looks great..also I did pull the gaskets and my squish gap Is right on ..so questions... Did you leave the shields on the crank bearings?? And how did the pz20 hold up??.....thanks and ride on 😎

[@LAHover]

So far so good on the PZ20. I did leave the shields on the crank bearings. It's not ideal IMO, but that's how it came so I'm going to run it.

[@jamesgnarkill3112]

@@LAHover I left the shields as well.. someone made mention of extra compression or volume pressure in these minerallis... besides if it did fail I don't think it would immediate failure...seems like we would have time for a replacement...

[@JustmePeter12]

My piston pin got eaten up by the bearing that's what making the noise I'm changing the pin ang piston

[@cesarpagan4640]

Was it stock Jets or did you change it?

[@cesarpagan4640]

With the PZ 20

[@daviddavis7448]

I have a question I have a 50 cc motor and it was running good like two weeks ago and then nothing got a brand new carburetor and I’m getting gas but I have compression and it wasn’t to fire up but nothing

[@daviddavis7448]

Any ideas

[@awakenotwoke2643]

Must be spark then,test magneto?

[@garypapesh1345]

Measure the width of the crank assembly, maybe it wasn’t pressed together completely

[@LAHover]

Good point! Thanks :)

[@mrnick8171]

wait why does ur 49cc have closed transfer ports the one i got has open transfer ports

[@LAHover]

Just the way it came. I don't have much experience with the 49cc kits

[@MrJasenstewart97]

I have a clone mz65 that's either a little larger or the same size as a real mz65 but it hits around 3k-4k rpm and hits damn hard. I also have a copperhead 65 pipe I tried and it hits harder but doesn't hit in the powerband until around 7k-8k rpm so I stuck with the clone

[@LAHover]

Might be a "Deluxe, or WC80" pipe. They are built about the same. Should do well for the price.

[@MrJasenstewart97]

@@LAHover I'm pretty sure it's a wc80

[@radiowavz]

What? No Red green in the background!

[@LAHover]

Seen every episode :) but I still play it from time to time because they just don't get old :D

[@sterman7632]

Never tap o the crankshaft with hammer

[@tb33man82]

I tried to join your discord and it says your invite expired

[@LAHover]

Thanks for the heads up. Here is a new one discord.gg/2VeMY3ch

[@HanzelFonferek]

1st and 1st like 👍

[@noxplanationgaming]

Get a thick case gasket

[@Garrettsbrokebuilds]

WHERE IS BURBER

[@erican442]

Look for thinner bearings.

[@LAHover]

Crank weights were not pressed together enough. But thanks for the tip :)

[@dannyoutlaw9919]

If just replace the case on the 49cc... that the only way to safely fix it

[@LAHover]

Thanks for the suggestion. It turned out to be that the crank was not pressed together enough.

[@dannyoutlaw9919]

@@LAHover oh wow... I'm glad you found it I know that's a load off your mind...

[@Felix_Edmundovich]

У вас тоже снег выпал.

[@bspyder4310]

5th

[@epicwinfacepie]

i say screw the 49cc

[@epicwinfacepie]

it was a really awesome video ideaa but that seems like way too much work for such a small amount of power. if you take it to a machine shop to reseat those bearings that might just total out the motor for the price.

[@kjohns1413]

I’ll have to agree. I never got enough power out of my 49cc 2 stroke to enjoy it.

[@motorizedbikestuff5339]

Junk that motor.scavange some parts and save your time.

[@LAHover]

Might just be the way to go. :) thanks.